John B Groot

US Patent:

6375074, Apr 23, 2002

Filed:

Feb 17, 1999

Appl. No.:

09/251568

Inventors:

LeRoy Dickson - Morgan Hill CA
John Groot - San Jose CA
Carl Harry Knowles - Morristown NJ
Thomas Amundsen - Turnersville NJ

Assignee:

Metrologic Instruments, Inc. - Blackwood NJ

International Classification:

G06K 710

US Classification:

23546201, 23547201

Abstract:

A holographic laser scanner for scanning bar code symbols, in which a plurality of scanning planes are projected through a plurality of different focal regions in order to provide, at each such focal region, a plurality of scanlines that are substantially confined within the highly-defined 3-D scanning volume of the holographic laser scanner. This remarkable capability of the system ensures that the scanlines of the holographic scanner extend only where scanning is required (e. g. , within the highly-defined 3-D scanning volume). This avoids scanning regions of space where bar code symbols are known to not be present, or collecting scan data from such âemptyâ regions of space. By virtue of the present invention, the highly-defined 3-D scanning volume of the holographic laser scanner can be easily positioned above a doorway, conveyor belt, loading dock or the like where objects bearing bar code symbols are expected to pass.

US Patent:

6415980, Jul 9, 2002

Filed:

Feb 11, 2000

Appl. No.:

09/503079

Inventors:

LeRoy Dickson - Morgan Hill CA
John Groot - San Jose CA
Carl Harry Knowles - Morristown NJ
Thomas Amundsen - Turnersville NJ

Assignee:

Metrologic Instruments, Inc. - Blackwood NJ

International Classification:

G06K 710

US Classification:

23546235, 23547201

Abstract:

A holographic laser scanning system for producing a highly defined 3-D scanning volume for omni-directional laser scanning of bar code symbols therein having a minimum element width on the order of about 0. 017 inches or less. The holographic laser scanning system comprises a housing, a plurality of laser sources, a holographic scanning disc and a plurality of photodetectors. The plurality of laser sources are disposed within the housing, for producing a plurality of laser beams. The holographic scanning disc is disposed within the housing, and has a plurality of holographic optical elements for scanning the laser beams and producing a plurality of laser scanning planes for scanning a code symbol. Each laser scanning plane has predefined beam characteristics and is spatially confined within a highly-defined 3-D scanning volume having at least three focal zones, a depth of field of at least 10 inches, and a scanning volume of at least 1,440 cubic inches. The plurality of laser scanning planes intersect within the highly defined 3-D scanning volume and the predefined beam characteristics of the laser scanning planes cooperate within the highly defined 3-D scanning volume so as to produce an omnidirectional laser scanning pattern for omnidirectional scanning therewithin, code symbols having a minimum element width on the order of about 0.

US Patent:

6422466, Jul 23, 2002

Filed:

Jan 7, 2000

Appl. No.:

09/479435

Inventors:

LeRoy Dickson - Morgan Hill CA
John Groot - San Jose CA
Carl Harry Knowles - Morristown NJ
Thomas Amundsen - Turnersville NJ

Assignee:

Metrologic Instruments, Inc. - Blackwood NJ

International Classification:

G06K 710

US Classification:

23546201, 23546234

Abstract:

A method of and system for automatically identifying packages during package transport operations carried out by a human operator walking through the doorway of a storage container parked up to a loading dock, wherein a laser scanning system is supported above the doorway defining a passageway of 3-D spatial extent, through which a human operator may walk while manually transporting packages bearing bar code symbols. In the illustrative embodiment, the laser scanning system includes a housing having a light transmission aperture, and a laser scanning pattern generator disposed within the housing. During operation of the system, the laser scanning pattern generator employs a holographic scanning disc to project through the light transmission aperture, an omnidirectional laser scanning pattern which is substantially confined within the spatial extent of a predefined 3-D scanning volume that spatially encompasses a substantial portion of the passageway. As each package bearing a bar code symbol is transported through the doorway as the human operator walks through the doorway, the package is automatically identified by the laser scanning system supported above the doorway. By virtue of the present invention, a bar coded package can now be automatically identified as a human operator holding the package walks through the doorway of a storage container, thus improving inventory control accuracy and worker productivity.

US Patent:

6439462, Aug 27, 2002

Filed:

Feb 18, 1999

Appl. No.:

09/252255

Inventors:

LeRoy Dickson - Morgan Hill CA
John Groot - San Jose CA
Carl Harry Knowles - Morristown NJ
Thomas Amundsen - Turnersville NJ

Assignee:

Metrologic Instruments, Inc. - Blackwood NJ

International Classification:

G06K 710

US Classification:

23546234, 23546238

Abstract:

An automatic bar code symbol reading system for automatically reading bar code symbols on packages transported along a conveyor belt through a 3-D scanning volume. The system includes a holographic-based bar code symbol detector and a bar code symbol scanner mounted above the conveyor belt. The holographic-based bar code position detector produces a first laser scanning pattern within the 3-D scanning volume, and scans each transported package, detects the position of the bar code symbol therein, and automatically produces bar code position data specifying the position of the detected bar code symbol. In automatic response to the produced bar code position data, the bar code symbol scanner is steered so as to collect light reflected off the detected bar code symbol, and produce scan data indicative of the detected bar code symbol. A scan data processor automatically processes the produced scan data so as to automatically read the detected bar code symbol and produce symbol character data representative thereof. By virtue of the present invention, it is now possible automatically detect the position of high-resolution bar code symbols on packages transported through a large 3-D scanning volume using a holographic-based bar code position detector, and collect high-resolution scan data from the detected bar code symbol using a steerable high-speed bar code symbol scanner, so that such collected scan data can then be subsequently decode processed in a high-speed manner, as required in numerous industrial scanning applications.

US Patent:

6457646, Oct 1, 2002

Filed:

Sep 17, 1999

Appl. No.:

09/398741

Inventors:

LeRoy Dickson - Morgan Hill CA
John Groot - San Jose CA
Carl Harry Knowles - Morristown NJ
Thomas Amundsen - Turnersville NJ

Assignee:

Metrologic Instruments, Inc. - Blackwood NJ

International Classification:

G06K 710

US Classification:

23547201, 23546201

Abstract:

The first scanner generates an omnidirectional laser scanning pattern within a large 3-D scanning volume in order to detect the location of a code symbol therewithin and produce data indicative of its location therewithin. Using this location data, the second scanner produces a high density scanning pattern to aggressively scan the region in which the code symbol has been detected, and collect scan data for decode processing. In the illustrative embodiment, the first scanner is realized as a multiple-focal plane holographic scanner, whereas the second scanner is realized as a high-speed 2-D scanner. By virtue of the system and method of the present invention, it is now possible to read bar code symbols located anywhere within very large volume of space, with a high degree of accuracy hitherto impossible using prior art techniques.

US Patent:

6464141, Oct 15, 2002

Filed:

Feb 18, 1999

Appl. No.:

09/252254

Inventors:

LeRoy Dickson - Morgan Hill CA
John Groot - San Jose CA
Carl Harry Knowles - Morristown NJ
Thomas Amundsen - Turnersville NJ

Assignee:

Metrologic Instruments, Inc. - Blackwood NJ

International Classification:

G06K 710

US Classification:

23546234, 23546201, 23547201

Abstract:

A bar code symbol scanning system for laser scanning bar code symbols within a 3-D scanning volume and automatically producing bar code symbol position information specifying the position of each bar code symbol detected within said 3-D scanning volume. The system comprises a laser scanning mechanism and a scan data signal processor. The laser scanning mechanism generates and scans a laser beam so as produce a laser scanning pattern which is substantially confined within a 3-D scanning volume having a plurality of focal planes. During system operation, the laser scanning pattern, consisting of a plurality of scanlines disposed within each focal plane, scans the bar code symbol on each object transported through the 3-D scanning volume. In response thereto, the laser scanning mechanism automatically produces scan data indicative of the scanned bar code symbol. Therewhile, the scan data processor processes the produced scan data so as to detect each scanned bar code symbol within the 3-D scanning volume, and produce bar code symbol position data specifying the position of the detected bar code symbol therewithin.

US Patent:

6474556, Nov 5, 2002

Filed:

Feb 17, 1999

Appl. No.:

09/251674

Inventors:

LeRoy Dickson - Morgan Hill CA
John Groot - San Jose CA
Carl Harry Knowles - Morristown NJ
Thomas Amundsen - Turnersville NJ

Assignee:

Metrologic Instruments, Inc. - Blackwood NJ

International Classification:

G06K 710

US Classification:

23546224, 23526225

Abstract:

An over-the-conveyor bar code symbol reading system for scanning bar coded packages transported through a 3-D scanning volume having a plurality of focal planes. The system comprises a conveyor belt, first and second laser scanning subsystems mounted thereabove, and a scan data processor. The first laser scanning subsystem generates a first laser scanning pattern above the conveyor belt for scanning each bar coded package transported therealong, and produces bar code position data indicative of the position of the bar code symbol on each scanned package. The second laser scanning subsystem generates and scans a second laser beam to produce a second laser scanning pattern within a 3-D scanning volume above the conveyor belt and having a plurality of focal planes. In response to scanning the transported package, the second laser scanning subsystem produces scan data indicative of the scanned bar code symbol thereon. This scan data is processed to detect each scanned bar code symbol and determine within which one of the plurality of focal planes the detected bar code symbol resides on the transported package.

US Patent:

6523750, Feb 25, 2003

Filed:

Nov 15, 1999

Appl. No.:

09/440560

Inventors:

LeRoy Dickson - Morgan Hill CA
John Groot - San Jose CA
Carl Harry Knowles - Morristown NJ
Thomas Amundsen - Turnersville NJ

Assignee:

Metrologic Instruments, Inc. - Blackwood NJ

International Classification:

G06K 0710

US Classification:

23546234, 23546232, 359 18

Abstract:

A holographic laser scanning system for scanning bar code symbols. The system comprises a holographic scanning disc having a plurality of holographic optical elements disposed thereon for scanning the plurality of laser beams directed at the same incident angle. Each holographic optical element as substantially the same Bragg angle. The parabolic light reflective surfaces are disposed beneath the holographic scanning discs. Each parabolic light reflective surface has an optical axis disposed off the Bragg angle of the holographic optical elements, for focusing towards a focal point above the holographic scanning disc, the reflected light rays collected by each holographic optical element. A photodetector is disposed at the focal point of the corresponding parabolic light reflective surface above the holographic scanning disc, and is radially aligned with the optical axis of one parabolic light reflective surface. The light diffraction efficiency of each holographic optical element at the angle of incidence of each laser beam during scanning is substantially greater than the light diffraction efficiency of the focused laser light transmitted from each parabolic light reflective surface through the holographic optical elements towards corresponding photodetector during light detection. This enables the collected light rays, focused by the parabolic light reflective surface, to be efficiently transmitted through the holographic optical elements, to the photodetector for detection and generation of a scan data signal for subsequent processing.